A novel visible light induced step-growth polymerization to form poly(phenylene methylene) by electrophilic aromatic substitution reactions is described.

No abstract

A novel visible light induced step‐growth polymerization by electrophilic aromatic substitution between photochemically generated carbocations and dimethoxybenzene nucleophile is described. Conventional step‐growth polymerization and chain‐growth condensation polymerization (CCP) mechanisms are presented. It is found that by changing the molar ratios of the monomers slightly, the CCP mechanism becomes operative and relatively higher molecular weight polymers are obtained because of the higher reactivity of the end groups of the intermediates and oligomers than that of the monomers. The possibility of grafting onto polymers containing epoxide at their side chains by photoinduced chain end activation of poly(dimethoxyphenylene methylene) is demonstrated. This study is expected to promote potential applications of the combination of photoinduced electron transfer reactions and CCP in macromolecular synthesis and material science.

3D printing technology offers solutions for numerous needs in industry and the daily life of individuals. In recent years, most research efforts have focused on this technology as the market share has grown and requirements have become specified in their related fields. In this work, a novel visible light induced 3D printing system with high resolution and short printing time using dimanganese decacarbonyl (Mn 2 (CO) 10 ) in combination with organic halides is reported. The radicals formed through halogen abstraction by photochemically generated manganese pentacarbonyl from organic halides with high quantum efficiency initiate the polymerization of acrylic resins. The kinetics of the process using various halide-containing molecules in the photoinitiaiting system are investigated with real-time fourrier transform infrared spectroscopy and photo-differential scanning calorimetry analyses, and the characteristics of 3D printouts are presented and compared with that of the commercial photoinitiator, 2,4,6-trimethylbenzoyl)phosphine oxide without Mn 2 (CO) 10 . The results obtained confirm that the combination of Mn 2 (CO) 10 and structurally diverse organic halides is a class of promising 3D system for various applications.

A new visible light induced step‐growth polymerization of dibromoxylene, and diols using dimanganese decacarbonyl and diphenyliodonium salt is described. The polymerization is suggested to proceed by substitution reaction between dixylenium cations formed upon visible light irradiation in the presence of dimanganese decacarbonyl and diphenyl iodonium salt. For the described substitution reaction with diols as nucleophilic component, the scope of the process is studied. Furthermore, the presence of halide groups at chain ends of the resulting polymers provided the possibility of initiating subsequent free radical and free radical promoted cationic resulting in the formation of polyether‐based block copolymers.